Stop mechanism



Sept. 18, 1956 J. P. MACKIE STOP MECHANISM 2 Sheets-Sheet 1 Filed March9, 1955 I Inventor JOHN P MHCKIE M h h 1 A tiorney Sept. 18, 1956 J PMAK|E I 2,763,035

STOP MECHANISM Filed March 9, 1953 2 Sheets-Sheet 2 Inventor J oHN PMama;

B 7% mail rM Attorney STOP MECHANISM John Pringle Mackie, AlbertFoundry, Belfast, Northern Ireland, assignor to James Mackie & SonsLimited Application March 9, 1953, Serial No. 341,227

Claims. (Cl; 19- 169) This invention relates to stop mechanisms fordrawing frames and similar textile machines such, for example, asspinning frames, in which sliver or other fibrous material emerging froma drawing head then proceeds to a further stage of treatment.

The most important of the faults occurring in the operation of such amachine and which may be detected by means of a stop mechanism is thedisruption of the sliver on its passage from the drawing rollers, andstop mechanisms employing a detector bearing on .the sliver over thispart of its travel are well-known. The usual form of such stop mechanismcomprises a detector which bears directly on the sliver in a fixedposition between the drawing rollers and, in a drawing frame forexample, the delivery rollers. In the event of disruption of the sliverin this region, the detector member passes through and beyond the normalline of travel of the sliver, and this movement is utilised to operate astop device.

Stop mechanisms of this general type are unsatisfactory for a number ofreasons. The sliver, particularly in a drawing frame of the finishertype, is extremely fragile and the detector is dependent on the strengthof the sliver to support its whole weight. This often causes a gradualsag in the sliver, and in consequence a build-up of vagrant fibres takesplace on the detector or between the detector and the moving sliver.This can then result in disruption of the sliver due to excessivefriction and to the excessive bearing area thereby produced between thedetector and the surface of the sliver.

This disadvantage can be partly overcome by the use of a very lightdetector, but this gives rise to a further disadvantage in that such adetector will not function until the sliver is completely disrupted. Itoften happens-that the sliver becomes partially broken and it is clearlydesirable that the stop mechanism should be brought into action undersuch conditions.

These disadvantages are overcome in accordance with the presentinvention by the use of a detector member which is repeatedly caused tomove relatively to the fibrous material in a closed path in such a wayas to engage the fibrous material over part at least of its path ofmovement, and which in the event of disruption of the fibrous materialhas its normal movement interrupted so as to operate a stopping device.

The substantially continuous movement of the detector avoids any suchbuild-up of vagrant fibres as previously mentioned, while at the sametime the detector is able to operate satisfactorily with only partialdisruption of the material. In practice, the departure of the detectormember from its normal path of movement causes either the member itselfor a part moving with it to engage a co-operating member and so operatethe stopping device. Preferably, the path of movement of the detectorruns generally parallel with the direction of movement of the fibrousmaterial, and the detect-or is caused to recipro cate along this path,being deflected from it to engage the co-operating member when thefibrous material is disrupted.

Patented Sept. 18, 1956 Although the path of movement is generallyparallel with the direction of movement of the fibrous material, it ispreferred that the detector should touch the material during only ashort portion of its travel. This has the effect of deflecting thematerial to the smallest extent and does not interfere with its normalpassage from the machine. The cooperating member preferably con sists ofan abutment so that when the detector departs from its normal path ofmovement, its motion is stopped by the abutment, and this is utilised tooperate a stopping device. This may be achieved by transmitting themotion to the detector from a driving member by way of aspring so thatwhen the motion of thedetector is stopped,- the spring is deformed. Therelative movement then occurring between the ends of the spring is usedto operate the stopping device.

Preferably the reciprocation of the detector is produced by a shaftrocked by a connecting rod driven from an eccentric. The drive from theconnecting rod is transmitted through a spring to a link mounted on theshaft so that when the motion of the detector, and hence the shaft, isstopped, the connecting rod is displaced inrelation to the link. Therelative motion between the ends of the spring is then used to produce acarnming action to operate a switch, and thus stop the machine. If thestop mechanism is to be used for a drawing frame cornprising a largenumber of separate drawing heads, the rocker shat-t may extend acrossthe whole width of the machine and carry a number of detectors, one foreach drawing head and co-opera'ting respectively with the sliver fromthat drawing head.

Although detection of disruption or the sliver or other fibrous materialis of primary'importance, anotherfault which may occur is caused bycho-king'of the sliver in its passage trom the drawing rollers.- in anumber of ways, such, for example, as failure of the drawingrollers topull the sliver through the machine at the correct drafting speed, withthe result that a-very ea'vy sliver is' delivered and causes anobstructionbetween the drawing rollers and the next part of the machine.This sliver mass quickly builts up and mayresult. in considerabledamage. A stop mechanismin accordance with the present invention mayfurther be utilised to operate on occurrence of a fault of this nature.

in order to achieve this, a second loo-operating member is provided withwhich the detector or a part moving with it moves into contact whendeflected by the-presence of the thickened sliver. in addition, adeflector plate or similar member is preferably located on the oppositeside of the sliver to the detector. Any choking that occurs then forcesthe sliver away from the plate, carrying the detector With it so as todeflect it from its path of motion in the opposite direction to thatcaused by the disruption 'of the sliver. This brings the detector intoengagement with the second co-operating member to stop the rim-- chine;

A stop mechanism, in accordance with the invention will now be describedin more detail, by way of example, with reference to the accompanyingdrawings, in which:

Figure 1 is a side elevation of the delivery and of a drawing frame;

Figure 2 is a plan view of the 'part shown in Figure 1;

Figures 3 and 4 are plan views of forms of detectors used in themechanism shown in Figures 1 and 2;

Figures 5 and 6 are side elevations of the detector in operation; and

Figure 7 is a side elevation of the detector and cooperating par'ts ofthe stop mechanism illustrating their operation to stop the machine uponthe breaking of a sliver.

Referring first to Figure. 1, sliver 1 is shown emerging This may becaused.

pins 4. The sliver passes over a sliver plate 5 in the usual way andthence between delivery rollers 6 and 7 to the next stage of treatment.It is during its passage between the drawing rollers and the deliveryrollers that faults in the sliver may most readily be detected. For thispurpose, a detector 10 bears on the sliver close to the point where itpasses over the sliver plate 5. The detector is pivotally mounted bymeans of a pin 11 to a bracket 12 turning with a rocker shaft 13, bestseen in Figure 2.

The shaft 13 is rocked by means of a connecting rod 14 connected to aneccentric 15 driven by meshing gears 16 and 17. The latter is mounted onthe shaft of the delivery roller 6 and the gears are enclosed within acasing 18. The rod 14 is free to slide through a bush 21 turning on theend of a link arm 22 rigidly mounted on the shaft 13, and is preventedfrom withdrawal from the bush 21 by means of a nut 23. The operativethrust is transmitted from the rod 14 to the bush 21 by means of acoiled spring 24 situated between the bush 21 and a collar 25 secured tothe rod 14. Thus, as the eccentric 15 rotates so the rod 14 transmits arocking motion to the link 22 causing the shaft 13 also to rock.

This rocking movement causes the detector 10, which is hearing on thesliver, to reciprocate in a direction parallel with the direction ofmotion of the sliver. The detector 10, however, is only in contact withthe sliver for a short portion of its travel, being lifted clear duringthe remainder of its travel by the engagement of an extension 26, whichengages with a camming surface 27 mounted on the frame of the machine asshown diagrammatically in Figure 5. Thus, the detector touches thesliver briefly during each stroke and any tendency to the build-up ofvagrant fibres is overcome. If, however, the sliver should break orbecome thin, the detector 10 is allowed to drop, and during the courseof its reciprocation a shoulder 28, formed in the detector, comes intoengagement with the edge of the sliver plate 5 as shown in Figure 7.This immediately stops the movement of the detector, and since this isrigidly connected to the shaft 13, the rocking of this shaft is alsostopped.

Consequently, the thrust of the rod 14 causes the spring 24 to becompressed, and the collar 25 moves towards the bush 21. This brings thesurface of the collar 25 into engagement with a cam surface formed onone side of an arm 30 pivoted to the bush 21 and provided with acounterweight 31, which normally tends to rotate the arm in ananti-clockwise direction. Movement of the collar 25 towards the bush 21rocks the arm 30 in a clockwisedirection and brings its opposite side tobear against the plunger of a small switch 32 mounted on a block 33attached to the frame of the machine. This opens the switch and stopsthe machine.

The stop mechanism is also designed to Work in the event of anabnormally thick sliver passing through, or if there is a choke to theleft-hand side of the drawing rollers which eventually passes through tothe delivery rollers. For this purpose, a deflecting plate is situatedbelow the path of the sliver to the left of the sliver plate 5 so thatwhen an extra thick body of sliver passes from the drawing rollers, thedetector 10 is lifted from its usual path of movement. This brings theextension 26 into engagement with a stop member 41 showndiagrammatically in Figure 6 and this again arrests the travel of thedetector. This stops the motion of the shaft 13 and causes the spring 24to be compressed so as to operate the switch 32.

Thus it will be understood that a single detector is arranged to operateeither in the event of missing sliver or in the event of abnormallythick sliver. In general, a detector of width corresponding to that ofthe sliver is used as shown in Figure 4. In some cases, however, ifthere is likelihood of part only of the sliver being missing,'thedetector may consist of two or more separate fingers. A constructionincluding. two such fingers is shown in Figure 3, and it will be clearthat if either one or the other of these two fingers drops below itsnormal path of travel owing to the absence of part of the sliver, itwill come into engagement with the edge of the sliver plate 5, andoperate to stop the machine in the manner already described.

I claim:

1. In a textile machine having a pair of drafting rollers, a sliverplate and a pair of delivery rollers, said drafting rollers feedingsliver over said sliver plate to said delivery rollers, the combinationof a detector, means for cyclically moving said detector so as to engagesaid sliver over part at least of its path of motion, said path ofmotion being such that if said sliver is missing said detector drops toengage the edge of said sliver plate stopping further motion thereof,and means responsive to stoppage of the motion of said detector forstopping the machine.

2. A textile machine according to claim 1 in which said means responsiveto stoppage of the motion of said detector comprises a yieldableconnection between said detector moving means and said detector, andmeans responsive to yielding of said connection for stopping themachine.

3. In a textile machine having a pair of drafting rollers, a sliverplate and a pair of delivery rollers, said drafting rollers feedingsliver over said sliver plate to said delivery rollers, the combinationof a rocker shaft, a radial arm projecting from said rocker shaft, adetector pivoted to said arm, means for rocking said rocker shaftwherebysaid detector is caused to reciprocate in engagement with saidsliver, the path of reciprocation being such that if said sliver ismissing said detector drops to engage the edge of said sliver platewhereby said rocker shaft is stopped, and means responsive to stoppageof said rocker shaft for stopping the machine.

4. A machine according to claim 3, in which said rock, ing meanscomprises an eccentric, means for driving said eccentric, a rodconnected to said eccentric, a second radial arm on said rocker shaft,and a spring trans: mitting the movement of said rod to said second arm,and in which said means for stopping the machine comprises cam meansresponsive to distortion of said spring consequent on stoppage of saidrocker shaft.

5. A machine according to claim 4 and including .an electric switchoperated by said cam means.

6. In a textile machine having a pair of drafting rollers, a sliverplate and a pair of delivery rollers, said drafting rollers feedingsliver over said sliver plate to said delivery rollers, the combinationof a rocker shaft, a radial arm extending from said shaft, a detectorpivoted to said arm, a second radial arm extending from said shaft, aneccentric, means for driving said eccentric, a rod connected to saideccentric, a spring transmitting the movement of said rod to said secondarm to rock said rocker shaft, whereby said detector is caused toreciprocate in engagement with said sliver, means for lifting saiddetector from said sliver during part of its reciprocation, the path ofreciprocation being such that if said sliver is missing said detectordrops to engage the edge of said sliver plate, abutment means situatedabove the path of reciprocation of said detector, said detector movinginto' engagement with said abutment means when the thickness of saidsliver increases, cam means responsive to distortion of said springconsequent on stoppage of said rocker shaft, and switch means operatedby said cam means to stop the machine.

7. A machine according to claim 6, in which said detector comprises aplurality of parallel fingers spaced across the width of said sliver.

8. A machine according to claim 6, and also comprising a deflector platesituated on the opposite side to said detector of said sliver.

9. In a textile machine including means defining a a path of travel offibrous material, the combinationof a pivoted detector, a mounting forsaid detector, support means for said fibrous material, said fibrousmaterial passing between said detector and said support means, means forproducing cyclically repeated relative motion between said detector andsaid support means, and means responsive to interruption of said cyclicrelative motion to stop said machine.

10, In a textile machine including means defining a path of travel offibrous material, the combination of a pivoted detector, a mounting forsaid detector, support means for said fibrous material, said fibrousmaterial passing between said detector and said support means, means forproducing a cycle of repeated relative motion between said detector andthe said support means so as to bring said detector into engagement withsaid fibrous material as it passes over said support means, failure ofsaid detector to encounter said fibrous material at that point resultingin an interruption of said cycle, and means responsive to saidinterruption for stopping the machine.

References Cited in the file of this patent UNITED STATES PATENTS1,205,506 Bentley Nov. 21, 1916 1,494,829 Woodcock May 20, 19241,556,018 Naumberg Oct. 6, 1925 1,735,102 Arragg Nov. 12, 1929 1,926,957Peck Sept. 12, 1933 2,611,230 Saunders Sept. 23, 1952

